Will referencing weakSelf from within a method called by weakSelf cause a retain cycle? [duplicate]

Question

This question already has answers here:

Does calling a method inside a block that calls another method referring to self cause a retain cycle? (2 answers)

Closed 9 years ago.

I think I understand how simple retain cycles are create but I don't fully understand more complicated situations.

Here is code that would cause a retain cycle. (right?)

[self.dataController loadInitialWithCompletion:^(BOOL dataChanged) {
    self.loading = NO;
}];

To avoid that retain cycle I would create a weak reference to self:

__weak typeof(self) welf = self;
[self.dataController loadInitialWithCompletion:^(BOOL dataChanged) {
    welf.loading = NO;
}];

I hope I'm correct so far.

Here's where it gets interesting. I have a method that calculates and caches text heights and then calls reloadData on a tableView. That method executes asynchronously and calls it's completionBlock (on the mainThread) when it's finished.

 __weak typeof(self) welf = self;
[self.dataController loadInitialWithCompletion:^(BOOL dataChanged) {
    [welf relayoutWithCompletion:^(CGPoint offsetBeforeReload) {
        welf.loading = NO;

        if (dataChanged) {
            [welf save];
        }

    }];
}];

Will this code cause a retain cycle because welf captures itself in the completionBlock for relayoutWithCompletion:? Am I correct in thinking that because welf is a weak reference I will avoid a retain cycle?

What if I took it a step further?

 __weak typeof(self) welf = self;
[self.dataController loadInitialWithCompletion:^(BOOL dataChanged) {
    [welf relayoutWithCompletion:^(CGPoint offsetBeforeReload) {

        if (offsetBeforeReload.y > 64) {
            [welf scrollToPoint:offsetBeforeReload completion:^{
                welf.loading = NO;
                [welf save];

            }];
        }

    }];
}];

It's welf all the way down...

Answer 1

No. Your weakSelf is a weak reference. Weak references do not cause retain cycles. That's the reason for using weak.